If I open up AF as my main text on my iPhone (Accordance 1.5) and then press the arrow on the split screen to choose a parallel text (obviously AF-E) it crashes. I can't replicate this behaviour when bringing up a parallel text with any other main text. It only seems to be a problem with AF.

I tracked down the 2nd edition module (AF), but am unable to reproduce the crash on our internal build of Accordance. I'll check against a release version as well, but at least we know that it is either unique to your installation, or fixed in the next update.

And, regarding the 3d edition, yes, I think it is definitely worth it. They updated the Greek text with new sigla, and the English translation was reworked. In Accordance we modified the layout of the modules to match a similar experience of the print edition; the Greek and English notes are separate modules, all symbols are contextually hyperlinked (meaning a manuscript in one book can mean different content for another book, and that is represented in the links).